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1.
Journal of Thermal Analysis and Calorimetry - Buckwheat starch is an alternative source to supply the high global demand for starch. The properties of starch can be modified through chemical and...  相似文献   
2.
包含SET结构域的核受体结合蛋白1(NSD1)是一种组蛋白甲基转移酶,它能够特异性的甲基化组蛋白H3赖氨酸第36位(H3K36).异常表达的NSD1主要发现于Sotos综合症患者体内,但它同样也能导致其他多种人类疾病的发生.目前已有靶向组蛋白甲基转移酶DOT1L和EZH2的小分子抑制剂报道,然而,靶向NSD1的化学探针分子尚未被发现.本文使用基于片段的核磁共振(NMR)筛选方法寻找到3个以NSD1蛋白作为靶点的苗头化合物,利用化学位移扰动分析技术测定了这些化合物与NSD1的结合亲和力.另外,利用分子对接方法选择获得苗头化合物与NSD1蛋白的最可能的结合模型.结果显示苗头化合物1结合于NSD1天然底物S-腺苷酸甲硫氨酸(SAM)的结合口袋中.我们的研究成果为进一步以结构为指导的从苗头化合物到先导化合物的衍化奠定了基础.  相似文献   
3.
During the course of a research program aimed at identifying novel antileishmanial compounds, a multi-gram synthesis of N-(trans-4-((4-methoxy-3-((R)-3-methylmorpholino)-1H-pyrazolo[3,4-d]pyrimidin-6-yl)amino)cyclohexyl)-2-methylpropane-1-sulfonamide ((R)-1) was required. This letter describes optimisation of the reaction conditions and protecting group strategy for a key Buchwald-Hartwig coupling, delivering the required quantities of (R)-1, as well as further compounds in the series.  相似文献   
4.
The constant emergence of new psychoactive substances is a challenge to clinical and forensic toxicologists who need to constantly update analytical techniques to detect them. A large portion of these substances are synthetic cannabinoids. The aim of this study was to develop a rapid and simple method for the determination of synthetic cannabinoids and their metabolites in urine and blood using gas chromatography–mass spectrometry. The method involves an ultrasound‐assisted dispersive liquid–liquid microextraction that implies a rapid procedure, giving excellent extraction efficiencies with minimal use of toxic solvents. This is followed by silylation and analysis with gas chromatography–mass spectrometry. The chromatographic method allows for the separation and identification of 29 selected synthetic cannabinoids and some metabolites. The method was validated on urine and blood samples with the ability to detect and quantify all analytes with satisfactory limits of detection (from 1 to 5 ng/mL), limits of quantification (5 ng/mL), and selectivity and linearity (in the range of 5–200 ng/mL). The developed assay is highly applicable to laboratories with limited instrumental availability, due to the use of efficient and low‐cost sample preparation and instrumental equipment. The latter may contribute to enhance the detection of new psychoactive substances in clinical and forensic toxicology laboratories.  相似文献   
5.
Environment-friendly electric vehicles have gained popularity and increased attention in recent years. The deployment of a network of recharging stations is essential given their limited travel range. This paper considers the problem of locating electronic replenishment stations for electric vehicles on a traffic network with flow-based demand. The objective is to optimize the network performance, for example to maximize the flow covered by a prefixed number of stations or to minimize the number of stations needed to cover traffic flows. Two integer linear programming formulations are proposed to model the problem. These models are tested on real-life traffic data collected in Denmark.  相似文献   
6.
7.
A variety of novel 2-alkylthiopyrimidines were synthesized through simple condensation of arylidenemalononitriles with different 2-alkylthiouronium halide derivatives catalyzed by anhydrous potassium carbonate (K2CO3). The reactions have been carried out under mild conditions in i-PrOH, and the products were obtained in moderate to good yields with a simple work-up method. Subsequently, some examples of these compounds have been converted into Tacrine analogs by applying the Friedländer reaction.  相似文献   
8.
Journal of Thermal Analysis and Calorimetry - A synthesis of a novel pharmaceutical cocrystal of the gemfibrozil (GEM) with the isonicotinamide (INCT) as coformer was carried out using the...  相似文献   
9.
Gas‐phase C―C coupling reactions mediated by Ni (II) complexes were studied using a linear quadrupole ion trap mass spectrometer. Ternary nickel cationic carboxylate complexes, [(phen)Ni (OOCR1)]+ (where phen = 1,10‐phenanthroline), were formed by electrospray ionization. Upon collision‐induced dissociation (CID), they extrude CO2 forming the organometallic cation [(phen)Ni(R1)]+, which undergoes gas‐phase ion‐molecule reactions (IMR) with acetate esters CH3COOR2 to yield the acetate complex [(phen)Ni (OOCCH3)]+ and a C―C coupling product R1‐R2. These Ni(II)/phenanthroline‐mediated coupling reactions can be performed with a variety of carbon substituents R1 and R2 (sp3, sp2, or aromatic), some of them functionalized. Reaction rates do not seem to be strongly dependent on the nature of the substituents, as sp3sp3 or sp2sp2 coupling reactions proceed rapidly. Experimental results are supported by density functional theory calculations, which provide insights into the energetics associated with the C―C bond coupling step.  相似文献   
10.
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, the Figures 6, 7, and 8 are in disagreement with their figure captions. Moreover, in the result...  相似文献   
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